Furnace



P 1945- T.-W. MUNFORD 2,384,764

FURNACE Filed Dec. 5, 1942 ZSmaentor M wmm (Ittorneg Patented Sept. 11, 1945 UNITED STATES PATENT OFFICE FURNACE Application December 3, 1942, Serial No. 467,816

2 Claims.

This invention relates to industrial heating furnaces of the type embodying internally fired U- tubes which extend out of the furnace chamber through a wall thereof and it is the object of the invention to provide improvements in means for interconnecting the tubes and furnace wall in a gas-tight manner where the tubes extend through said wall to the end that the tubes may be readily removed and replaced in the case of repairs.

In the accompanying drawing forming part of this specification,

Fig. 1 is a vertical section of a portion of a furnace embodying U-type heating tubes which depend from the top wall of the heating chamber, and

Fig. 2 is a vertical sectional view showing the improvement of the present invention.

In the drawing, 5 indicates a portion of the inner face of a side wall and 6 and l a portion of the top and bottom walls of a furnace cham- U-type combustion tube whose legs are indicated at 8 and 9. The top ends of these legs extend out of the chamber through the top wall thereof. A burner l discharges fuel downwardly into the leg 8, the burner being shown as comprising a fuel discharge tube II which extends some distance into the leg from a chambered body [2 to which fuel is delivered by a supply pipe l3. The air for supporting combustion of the fuel is drawn into the top end of the leg 8 by draft through the tube, the draft being produced by an exhaust pipe [4 which leads from the upper end of the leg 9 to a suction fan not shown. Means not shown will ordinarily be provided for igniting the fuel discharged from the burner tube II.

In the present invention the adit and exit ends .of the U-tube are each provided with an exterior circumferential groove IE to receive a split ring ll; of greater external diameter than the external diameter of said ends whereby the radially projecting portion of the ring may seat on a circumferential ledge ll formed by a top counterbore in an apertured body or mounting plate l8 seated against the metal backing 6' of the wall 6 and held in place on said backing as by a peripheral weld 20. Insertion of the ring in and removal of the same from the groove l may, of course, be readily accomplished when said groove is at a level above the top level of the mounting plate. When the ring rests on said ledge the tube will, of course, be suspended by said ring.

The top of the counterbore in the mounting plate l8 diverges outwardly to provide a space for packing material 2| to provide a substantially gas tight joint between mounting plate and upper end of the tube. The packing material is held in place by a clamping ring 22. It will be observed that although each clamping ring overlies the projecting end of the tube there is sufficient clearance between the two to permit a limited free upward movement of the tube such as may be caused by difference in expansion of the two legs of the tube.

The clamping ring for the exhaust end of the tube may constitute the bottom flange of a tubular fitting 23 which connects said exhaust end with the exhaust pipe l4 whereas the clamping ring for the firing end of the tube is preferably separate from the burner mounting which has been shown as comprising brackets 24 extending upwardly from a base ring 25 seated on the clamping ring.

From the foregoing description it will be seen that the present invention offers a relatively simple and practical way of providing a readily separable connection between an internally fired combustion tube and the furnace wall through which it extends.

What I claim is:

1. The combination with a furnace chamber and a combustion tube therein which projects out of the chamber through a bore in a wall of said chamber, of means for interconnecting said tube and wall at the bore comprising an annular key of greater external diameter than the diameter of said bore, an exterior circumferential groove in the projecting end of the tube wherein said key is removably confined, a seat on the outer side of said wall about said bore for engagement with the projecting portion of said key, and means for holding the projecting portion of said key to said seat.

2. The combination with a furnace chamber and an upright combustion tube therein which projects out of the chamber through a bore in the roof thereof, of means for interconnecting said tube and roof at said bore comprising an annular key of greater external diameter than the diameter of said bore, an exterior circumferential groove in the projecting end of said tube wherein said key is removably confined, a seat on the exterior side of said roof about said bore for engagement with the projecting portion of said key, and means for holding the projecting portion of said key to said seat.

THEODORE W. MUNFORD. 

